Filter bags for ground coffee



March 19, 1968 A. P. PETROZZO FILTER BAGS FOR QROUND COFFEE 2 Sheets-Sheet 1 Filed Jan. 17, 1967 FIG. 6.

a? r m 0 my No ER m p P E N N A FIG. 2.

ATTORNEY I March 19, 1968 I PETRQZZO 3,373,677

FILTER BAGS FOR GROUND COFFEE I Filed Jan. 17, 1967 v 2 Sheets-Sheet 2 FIG. 8.

INVENTOR ANNE P. PETROZZO ayiomw/ ATTORNEY United States Patent 3,373,677 FILTER BAGS FOR GROUND COFFEE Anne P. Petrozzo, 8814 Colonial Road, Brooklyn, N.Y. 11209 Filed Jan. 17, 1967, Ser. No. 609,851 3 Claims. (Cl. 99295) ABSTRACT OF THE DISCLOSURE Brief summary of the invention The bags when sold prefilled have circumferential stitching all around near the outer edge, and when sold empty have such stitching only part way to leave an inlet for filling. In all cases they also have circumferential stitching around the central opening. The bags are supplied in various diameters appropriate to the diameter of the percolator cup or the like in which they are to be used. With a pinked circumferential edge, when the bag is placed in the cup the outer circumferential seam is very close to the cup wall and the radial elements consequent to the pinking are bent upward against the wall of the cup, thus tending to direct the water issuing from the riser on the bag surface below which are the ground coffee granules. The central opening registers about the riser and the radial elements of the pierced opening likewise are bent upward against the riser, thus also directing the water over the bag. In the modification mentioned, the tab. is doubled back over the bag with the riser passing through the pierced opening therein, and the bent tab thus closes the inlet and also tends to lock the bag in place.

In the drawing, FIG. 1 is a prefilled with coffee granules.

FIG. 2 is a view similar to FIG. 1 but showing the annular space within the bag divided into two equal parts by a diametrical seam.

FIG. 3 is a sectional view FIG. 2.

FIG. 4 is a view of a filter bag which is empty and is provided with an inlet for filling it.

FIG. 5 is a sectional view taken on the line 55 of FIG. 4.

FIG. 6 is a fragmentary enlarged sectional view of the cup of a coffee percolator showing how any of the bags of FIGS. 1, 2 and 4 are mounted therein.

FIG. 7 is a view showing a modified empty bag provided with an inlet and radial extension tabs extending from both walls which define the inlet.

FIG. 8 is a sectional view taken on the line 88 of FIG. 7.

FIG. 9 is a view of the bag of FIG. 7 showing the radial extension tab folded down upon the bag.

.FIG. 10 is an enlarged sectional view showing a fragment of a percolator cup with the bag of FIGS. 7 and .9 mounted therein.

Although the bags disclosed herein are particularly adapted for use in percolators, they may also be used in other coffee makers, such as, for example, drip types, as will become apparent.

Referring in detail to the drawings, the numerals 10 view showing a filter bag taken on the line 3-3 of and 11, FIGS. 1-6, indicate two mutually identical discs of thin tissue having a high degree of wet strength and capable of fast filter action. Such filter tissue or material is readily available on the market.

The two discs 10 and 11 are mutually superimposed and united by a circumferential seam or the like 12 near their edges as well as by a second concentric seam 13 of greatly reduced diameter. Thus, in the case of the bag 14, FIG. 1, an annular chamber 17 is provided between the two 'discs, in which ground coffee, shown in the drawing as a multiplicity of dots, is contained.

In the case of the bag 15, FIG. 2, the two discs 10 and 11 are additionally united by two aligned radial seams 18 and 19 extending between the seams 10 and 13, thus dividing the space between the discs into two separate semi-annular chambers 20 and 21. This division of the space into two chambers or compartments assures equal distribution of the coffee granules on both sides of the dividing seams 18, 19.

The bags 14 and 15 are both marketed pre-filled with ground coffee and the seam 12 is applied either in whole after the granules have been positioned between the discs or, the seam may first have been extended part way around the discs to leave an entrance for admitting the granules whence the seam is continued the remainder of its length to. seal the bag.

In the case of the bag 16, FIG. 4, the seam 12 extends only part way around the discs to leave an unsealed or open portion 22 which provides an entrance mouth 23, FIG. 5, for entry of the coffee granules. This bag is sold empty so that the buyer may enter into it the desired measure of granules dictated by his taste.

All of the bags disclosed herein are intended primarily to contain a one-cup quantity of brewed coffee, so that when more than one cup is desired an additional number of bags is used in the manner described below.

The bags 14, 15 and 1 6 are all shown having pinked circumferential edges, with a consequent plurality of circumferentially equidistantly spaced pointed radial tabs whose bases are close to but slightly spaced from the seam 10. The bags also have, within the circular seam 13, a plurality of cuts, slits or tear lines 25 radiating from the center of the discs 10 and 11 to points near but spaced slightly from the seam 13.

FIG. 6 illustrates how any of the bags 14, 15, 16 are positioned in the well or bowl of a coffee percolator of a common type provided with the usual water pipe, or riser 26. Since the illustration in FIG. 6 is representative of all of the bags 14, 15, 16, the bag shown therein has been designated by the numeral 50 which therefore represents any one of these bags.

The diameter of the seam 12 is approximately that of the bowl 27 of the percolator, so that upon laying a filled bag in the bottom of the bowl the tabs 24 are bent upward. While the filter material is dry it is relatively stiff but flexible, so that these tabs are urged outward against the wall 28 of the bowl 27. While thus inserting the bag into the bowl, the upper end of the riser 26 parts the tabs 29 defined by the slots 25 and thus provides a central opening through the bag. Thus the tabs 29 are urged outward against the riser.

As the heated water in the percolator rises in the pipe 26 and percolates out of its upper end and falls upon the bag 50, the falling water is guided away from the wall 28 on to the surface of the bag below which the coffee granules are contained. The same is true of the water which descends down along the riser, as the tabs 29 likewise guide the water on to the bag surface. As soon as the filter tabs 24 and 29 become wetted they in fact cling to the surfaces of, respectively, the wall 28 and the pipe 26. As a consequence, little if any of the percolated water may escape through the perforations or passages 30 in the floor of the bowl 27 without encountering coffee granules. Hence a more efficient utilization of the ground coffee is assured.

All of the bags 14, 15 and 16 are provided with a string or strings 31 for lifting the used bags from the bowl 27. In the case of the bag 16 in which the entrance mouth 23 is provided for home filling, it is to be noted that it is not necessary to close or seal this mouth to prevent granules from leaking out through it. For when the bag is pressed down into the bowl 27, the tabs 24 thereon will all, including those extending from the disc portions which define the mouth, be bent upward against the wall 28 in the manner described so that their mutual overlapping will close the mouth.

The modification shown in FIGS. 7-1O is a bag suitable for marketing both as a pre-filled bag or an empty bag for home filling, but again it is intended primarily for a one-cup brewed coffee measure and therefore, when marketed filled, it is relatively thin and flat. This form of bag is a modification of that shown in FIGS. 4 and 5, and parts identical to those shown in FIGS. 4 and 5 are identically numbered while wholely modified but equivalent parts bear the same reference numeral followed by the suffix a. Both discs a and 11a have mutually superimposed elongated radial extensions or strips 32 whose length somewhat exceeds the radius of the discs. The circumferential seam 12 extends part way around the discs to leave an unsealed portion 22a, and it is from the two walls of the entrance mouth 23a that the strips 32 extend. Near the outer ends of the strips, mutually aligned cuts, slits or tear lines 25 are provided in the same manner as those previously described, to provide pointed tabs 29a.

The bag illustrated in FIGS. 7-10 is designated as a whole by the numeral 33, and FIG. 10 illustrates how it is set into the bowl 27 of a percolator. After the ground coffee has been passed into the bag through the mouth 23a in an obvious manner, the circular portion of the bag is mounted on the floor of the bowl in the same manner as previously described. Then the combined strips are doubled back and down against the upper disc 10a with the riser 26 piercing the slitted opening provided by the tabs 29a. As before, the tabs 24 extend upward against the wall 28 of the bowl while the tabs 29a extend upward against the tabs 29 (not shown in FIG. 10) which, as before, extend upward directly against the pipe. The bight 34, FIGS. 9 and 10, securely seals the mouth 23a. Pull strings are not attached to the bag 33, as the bag may be lifted out by grasping the strips 32. It is obvious although not specifically shown, that having but a single strip 32 extending from the lower disc 11a will also permit of closing the mouth 23a upon insertion of the bag as described into the bowl 27.

In case of coffee makers which have bowls provided with perforated floors but lack a riser projecting upward through the floor, the instant bags may be applied by laying them on the floor in the manner described above. In the absence of the riser, however, to bend upward the tabs 29 and/or 29a they remain fiat and undisturbed whence such portions provide a closure for the pierceable openings.

In reference to the home fillable bags provided with an entrance mouth illustrated in the drawing, it is believed that the seam 12 should extend through a distance of approximately five-sixths of a complete circle, leaving onesixth as the width of the mouth.

I claim:

1. A filter bag for coffee, for installation in a coffee maker having a bowl provided with a perforated floor and a centrally positioned water riser extending upward through said floor, the bag comprising two mutually superimposed discs of filter tissue having a first concentric seam therethrough near but spaced from the circumferential edges thereof and extending at least through approximately five-sixths of a circle and a second smaller concentric seam extending through a fullcircle around the center of the discs, said seams binding said discs together and forming an annular chamber therebetween adapted to contain ground coffee, the area within said second seam having a plurality of slits through said discs extending radially from the center thereof to a position close to but spaced from said second seam thereby defining a pierceable opening formed of radially inwardly extending tabs, the border portions of said discs which lie radially outward from said first seam having a pinked circumferential edge thereby providing a plurality of radially outwardly extending tabs, the diameter of said pierceable opening being substantially equal to the external diameter of said riser and the diameter of said first seam being substantially equal to the internal diameter of said bowl whereby when the bag is installed in the bowl on said floor said firstnamed tabs extend upward around said riser and said second-named tabs extend upward around the wall of the bowl whence all of said tabs direct water issuing from the riser toward the portions of the bag which define said annular chamber.

2. A filter bag according to claim 1, said bag having two mutually aligned radial seams extending between said first and second seams thereby dividing said annular chamber into two equal halves.

3. A filter bag according to claim 1, said discs having elongated radial strips of like dimensions extending from those edges thereof within the remaining approximately one-sixth of said first-named circle, said strips having a width greater than the diameter of said riser and a length greater than the radius of the discs, said strips having aligned pierceable openings therethrough positioned outward from the circumferential edges of the discs a distance substantially equal to the radius of the discs and being adapted to be doubled back upon the bag with said riser piercing said last-named pierceable openings.

References Cited UNITED STATES PATENTS 1,454,739 5/1923 Holland 99295 X 1,947,523 2/1934 Hirschhorn 99295 X 2,460,735 2/ 1949 Carroll 99295 X 3,083,100 3/1963 Baran 99-295 X WILLIAM I. PRICE, Primary Examiner. 

